<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div id="aa">sdfds</div>
<script type="text/javascript">
    var ul=document.getElementById('aa');
//    var li=ul.getElementsByTagName('li');

    console.log(aa.firstChild.nodeValue);
</script>
</body>
</html>